<!DOCTYPE html>
<html>
<body>
<p>Write something in the text field and press the Reset button.</p>
<form onreset="myFunction()">
<input type="text" id="myInput">
<input type="reset">
</form>
<script>
function myFunction() {
var x = document.getElementById("myInput");
alert("Before reset, the text was: " + x.value);
}
</script>
</body>
</html>